The radial distribution analysis of Bi2Se3, Sb2Te3 and Bi2Te3 in the liquid state is performed by neutron diffraction. The atomic distribution of amorphous Bi2Se3, film is also investigated by electron diffraction measurements. A considerable difference of the atomic arrangement in the first and second neighbour shells is observed between their liquid and crystalline states. It is suggested from the experimental result that these liquids have a tetragonal local order departing from the octahedral symmetry in the crystalline state. The interatomic distance and the coordination number for amorphous Bi2Se3 are 2.67 and 3.5 A, respectively, which are rather smaller than the corresponding values in the crystal. This fact indicates that this chalcogenide becomes more covalent on making amorphous. Mittels Neutronenbeugung wird eine Analyse der radialen Verteilung von Bi2Se3, Sb2Te3 und Bi2Te3 im flüssigen Zustand durchgeführt. Die atomare Verteilung von amorphen Bi2Se3-Schichten wird ebenfalls mittels Elektronenbeugungsmessungen untersucht. Ein beträchtlicher Unterschied der Atomanordnung in den ersten und zweiten Nachbarschalen zwischen den f lüssigen und kristallinen Zuständen wird beobachtet. Es wird aufgrund der experimentellen Ergebnisse angenommen, daß diese Flüssigkeiten eine tetragonale lokale Anordnung aufweisen, die von der Oktaedersymmetrie im kristallinen Zustand abweicht. Der interatomare Abstand und die Koordinationszahl für amorphes Bi2Se3 betragen 2,67 bzw. 3,5 A, die etwas kleiner sind als die entsprechenden Werte im Kristall. Dies zeigt, daß diese Chalkogenide nach der Amorphisierung kovalenter werden.
Abstract The electrical conductivity, the magnetic susceptibility, and the thermoelectric power of the liquid TI‐AgTe system have been obtained as functions of temperature and composition. The thermodynamic properties of the system have also been determined by means of the EMF method. The system shows a sharp minimum in electrical conductivity and a marked maximum in diamagnetic susceptibility at the stoichiometric composition of AgTlTe, where the change in sign of thermoelectric power also appears. These electronic properties are discussed in the light of current transport theories employed in the amorphous and liquid semiconductors. Further, the presence of the local order around the stoichiometric composition in the system is discussed by the support of the results of thermodynamic properties.
Measurements of electrical conductivity, magnetic susceptibility and thermoelectric power of the liquid Tl–CuTe system were carried out over wide temperature and composition ranges. The composition dependences of the electronic properties investigated exhibit that there are a deep minimum in electrical conductivity, a sharp maximum in diamagnetic susceptibility and a rapid change in the sign of thermoelectric power around 50 mol%Tl, which are considerably similar to the case of the well-known compound-forming liquid system, Tl–Te. These experimental results suggest that the localization of valence electrons is very remarkable at the stoichiometric composition of CuTlTe in the present system. In fact, the g-factor at this composition calculated by the strong scattering model is lower than 1/3 which is often used as the limiting condition when electrons in disordered systems begin to be localized. Furthermore, it is also expected through the application of the pseudogap theory to observed values of the electrical conductivity and the thermoelectric power that the carrier band structure has a marked asymmetric form in the vicinity of 50 mol%Tl in this system.
The magnetic susceptibility of liquid Ag–As 2 Se 3 system have been analyzed under the assumption that the paramagnetic susceptibility is attributable to the formation of dangling bonds. The diamagnetic susceptibility due to the ion core have been estimated in order to discuss the bonding nature and suggests that liquid Ag–As 2 Se 3 system has a strong covalent bonding nature in As 2 Se 3 -rich region. The activation energy and the entropy of the formation of dangling bonds have also been estimated and these value decreases with increasing the concentration of Ag. These results are attributable to the destruction of As–Se network structure by the addition of Ag and the covalent bonding nature of overall network is gradually changed with composition.
Abstract In both the liquid title systems an anomalous behavior in electrical properties can be observed around the stoichiometric composition SbTl 3 X 3 .
An order-disorder transition of Ag3In was investigated by means of specific heat, electrical resistivity and magnetic susceptibility measurements, and X-ray diffraction using an Ag-25at% In alloy. Specific heat vs. temperature curve shows a λ-type anomaly with a maximum at 214°C, and the heat of transition was found to be 220 cal/g-atom. From the X-ray analysis, no difference is found in the axial ratios between the low-temperature and high-temperature phases. From the result of magnetic susceptibility, a minor change in the electronic structure was suggested.
The gold standard for evaluating kidney function is kidney inulin clearance (Cin). However, this procedure is difficult to perform in patients with neuromuscular disabilities and/or bladder dysfunction. We aimed to develop a simpler method for determining the estimated glomerular filtration rate (eGFR) using equations and values for three biomarkers: serum creatinine (sCr), serum cystatin C (cysC), and serum beta-2 microglobulin (β2MG). This study evaluated three eGFR equations in patients with severe motor and intellectual disabilities (SMID).We evaluated the equations using data of 18 adult SMID patients with a clinical need for creatinine clearance (Ccr). We compared the results of each equation with Ccr-based eGFR instead of Cin using mean error (ME), root mean square error (RMSE), and P30.Based on eGFR, the ME values of Cr, cysC, β2MG, and Ccr were 74.5, 2.3, and 6.5 mL/min/1.73 m2, RMSE values, 92.3, 25.7, and 33.4 mL/min/1.73 m2; and P30, 16.7%, 77.8%, and 72.2%, respectively.eGFR-Cr cannot be used to reliably assess kidney function in adult SMID patients. It is better to use eGFR-cysC to evaluate kidney function in this patient population.
